This invention relates to an article conveyor that includes a plurality of carrier bars attached to a rotating conveyor belt. In particular, this invention relates to a quick-release pin for releasably fastening the carrier bars to the conveyor belt. Furthermore, this invention relates to a method for releasably fastening a bar-like member to a quick-release pin having a flexible member.
FIG. 1 discloses a prior art conveying mechanism 10 having a plurality of carrier bars 12. The plurality of carrier bars are mounted on a rotatable chain 14 that is powered by an independent powering mechanism (not shown). The conveyor bars are guided through a printing assembly 16 that prints indicia on individual articles that are contained in carrier bar pockets 18 located on each of the carrier bars. The articles are vibrated by a vibrator 17 to promote proper positioning.
In operation, the carrier bars often require removal for repair, replacement or cleaning as a result of ink spillage in station 16.
One solution to cleaning or repairing each of the carrier bars was to detach each of the carrier bars from the rotatable chain 14, by unscrewing clamping members, such as screws or bolts, from support platforms 20 of each of the carrier bars 12. However, this operation was very time consuming and inefficient.
According to FIG. 1, the carrier bars 12 are mounted onto the support platforms 20 using a pin 22, details of which are shown in FIG. 1A. Each pin 22 includes a centrally located groove 24 that is intended to cooperate with a pair of spring loaded ball bearings 26 located within the carrier bar on opposite sides from each other along groove 24. Each of the spring loaded ball bearings 26 is mounted in a threaded hole 28 of each of carrier bar. Accordingly, such a construction requires detailed machining of threaded holes 28 in order to positively lock the spring loaded ball bearings 26 into the groove 24.
FIG. 1B illustrates yet another prior art attempt to facilitate the removal of carrier bars. A pin member 40, similar in construction to the pin 22, includes a groove 42 for receiving a c-clip 44. The c-clip 44 is made from a rigid material and is difficult to bend to fit inside the groove 42. Furthermore, the inner diameter 45 and open ends of the c-clip include sharp edges 46 that scrape against the pin 40 and the carrier bar holes, thus increasing friction and causing difficulties in removing/installing the carrier bar onto the pin and c-clip arrangement. Moreover, the scraping action creates metal shavings, which are particularly undesirable when the conveyor is used for transporting editable articles or pharmaceuticals, which requires adherence to stringent governmental regulations.
In operation, with either the ball bearings 26 or the c-c-clip 44, a selected carrier bar of the plurality of carrier bars 12 is aligned with an alignment arrow 30 along the side of the conveying system. When the selected carrier bar is centered on the alignment arrow 30, an actuation lever 32 is rotated to cause a shaft 34 located below the surface of the conveying belt to rotate. Rotation of the shaft 34 pivots arms 36A and 36B, each of which is fixedly mounted to the shaft 34. Each of the arms includes a freely rotating roller 38A and 38B that contacts the selected carrier bar and applies a force sufficient to oppose the force of the c-clip 44 or the spring loaded ball bearings 26, thus causing the ball bearing or c-clip to retract within the groove and allowing removal of the selected carrier bar. This arrangement has the drawback that a significant force is required for removing the carrier bar because the uneven frictional resistance of the c-clips causes the carrier bar to be canted during removal, thus making the removal process difficult.